Devices for separating raisins from admixed stems



DEVICES FOR SEPARATI NG RAISINS FROM ADMIXED STEMS Filed Sept. 10, 1954 M. N. MUSGRAVE March 4, 1958 3 Sheets-Sheet 1 A rroe/vm March 4, 1958 M. N. MusGRAvE 7 2,825,454

DEVICES FOR SEPARATING RAISINS FROM ADMIXED STEMS Filed Sept. 10. 1954 s Sheets-Sheet 2 lug ung xwazugg INVENTOR. M'PE/LL M Musaeav;

' qgm March 4, 1958 us v 2,825,454

DEVICES FOR SEPARATING RAISINS FROM ADMIXED STEMS Filed Sept. 10, 1954 5 Sheets-Sheet 3 MERE/Ll N #4115664 V' W. fieibmw A TTOEA/EVS' g INVENTOR.

' as described, .will of necessity rather than engaging thereini t a a t; t,

, In'the alignment of the stems the fact that thespacing betweentthe ridges is materially'le'ss than thetlength of V t the long, crooked ste'm'sz;

but their "subsequent separation "stitutes' no particulartp'roblem' j 1 feedform. 1

t somewhat diagrammatically shown and broken away in it part; of the entiremachine in a representative 'gravity Figure 2 is an enlarged sectional view lengthwise of amachine, illustrating primarily the initial and the final portions of that channel.

Figure 3 is a transverse sectional view on the line 3+3 the line ka ofthatsametfigure; l

Figured is a view generally comparable of Figure 2, and Figure 4 is a similar sectional-view on with Figure 1,

i illustrating diagrammatically a positive feed form.

According to the present invention thefrnass of stems it and raisins is deposited upontheupper edges of aseries of parallel ridges The strips or blades 'which define j these'ridges' are spaced apart by .a distance -WhiiChBXC6dSji the greatest dimension of the largestjraisins, butlwhich is "much, less than the length of the *rnajority of stems. Provision is madef or'a'dvan'cing the deposited" mass along the ridges, and meanwhile the ridges and the V stems thereon are vibrated or otherwise agitated to'shake the mass apart. The'feed may be accomplished by gravi- 'ty or by positive feed means.

vibration during their advance is to'shake loosersome of the stems and to cause thesestemsto drop 'down'into The first etfectfof' the thetdirection o'fadvance along'a single channel of'such the channels between ridges; The provision is made for limiting their dropping and for causing thestems, as they continue to advance, to align themselves generally, in the direction of their advance, andito insurethat they are not pointed downwardly; Raisinswhich dropout-at the same time are 'also caught and caused to advance to a "further point Where they may be discharged through the Zscreern QBy the time the stems reach the raisin-jescape, apertures the stems have'bee n aligned in thetdirectionjof adva nce, and the raisin-escape apertures are ofsuch COD, a

struction, and'so'arranged, that the stems, when tarranged ride; on past theapertures most of thestems is of material importance. This prevents any stems' from .dr'oppingdown into the channels between the ridges while oriented in any directionexcept parallel with the ridges" and the ridge-forming elements.

' toifeedit upwardly- The machine of this inventionfin a'representativ'e q l form shown in Figure l, 'inclu des a shaking frame which has two vertically disposed side plates 9 of adequate tmass,.stuspended at 'their ends by rods-90 and spring means 9 1 from a fixed framework, indicatedtypically at A'motor 8 drives "pulleys 80 at opposite sides" of the yibrating frame through a belt 88, to rotate wheels t 1 81 provided with unbalanced weight masses 82, to'effect vibration'o'f theframe; {By changingthe, weightlmas st the amplitude at any given rate of drive 'may, be varied, in'lmown manner. The sense 'of'rotation of,the wheels 81 should be counterclockwiseyasviewed in Ftgure ll,

1 for reverse rotation tends to hold back thefmass, oreven V A feed chute 93 delivers the.,n1ixed raisins and stems' to be processed onto one end of a screen, such as will be 31. described in detail shortly, and at the opposite, discharge end of the screen the stems are delivered toya' stemide-l livery chute'94, and the separated raisins to a rais n d6? livery chute '95. For a purpose which will appe'ar'shortly, and optionally, alblowe r or*fan*7, driven by a niO-j tor79, delivers air by means of a duct 71 to a plenum chamber 72 which is incorporated in the vibrating s creenr 7 below a portion of its bottom. I

The sidefianges of the screen are 'indicated' at '19, and

7 its bottom is divided into two bottomtareas, an"initiallyi encountered areatgenerally indicated at A" andv a'sub- T sequently encountered areagenerallyindicatediat B: For 7 convenience, c'onsideringtheislcreen to'be ineli'nedi asgin 'Figure l for gravityadvance, these maybe termed, re-f spectively, the, upper and the :lower area, The upper a'rea' rnay, be solid, ,o'r mayi have slits' fo'r air ijetsf issuing from the plenum chambe'r:72, but primarilythe-upper'=:bottom 7 area A maybe considered as substantially imperfor'ate;

*The lowerrbottom area B,'however,"is constitutedpt'ii marily by louvers'; of a particularyform, through:vwhich raisins pass by gravity-to droptuponi a pan 18,';which,con j stitutes part of the screen, and-which leads t0 the raisinfl" delivery chute 5. It will be clear fromithe drawingsthatf as:

thebottorn area' A constitntes'only a small portionofthe' entire bottom areafand that thefbottom area B constitutes,

j Furthermore, though they may initially drop down :into

' downwardly, the provision of means to cause the stems to,

alignjthernselves with" the direction or advance, while' ing stems to enter tthe raisin-escape aperture which the stems encounter in common with the raisins, fis'ubse- :que'ntly. t 7 l j 1 j 5 t t 7 The nature and disposition of thefelements whichform' f the raisin-escape apertures are likewise importentir'lhese' are arranged in the formijofparallel,louvers disposed :t'ran'sverselytof the direction of advance, and constituting as a whole a bottom' area otthe screen; The raisins I v trolldown" onto these louver-s, or areiadvanced 'until they'i; freach; the, louveraperturesg These louver-forming ele- 1 '7 rnents are inclined reversely totthe'directionflof advance, rwhe'reby the raisinsfeven ithough they may be" rolling down the screen, if'the latter is"inclined," willreverse di 'rection and exit through. the louver-s, whereas the stems i will merely rideiov'er the inclinedlouvers and not engage therewith norLhang up. Moreover, thet'spacing 'between the louver elements is only' .sufficienti to pass the largest a further proeess contheyadvancefthrough:thisfinitial portion of theirs ad Vance, insures that there willtbe no downwardly project;

7 7 over' the louvers 1 by farthemajor portion of the bottom areaof the 'sereen;

t The only 'reason the louvers do-not constitute the ent ire 7 bottom area is that the drag of any dqwnwardlyj'pointed" stems on the substantially imperforatel'bottom arafiA is relied upon to detlect these stems,.so thhhtheywillride ofthearea B, when they-reach ithispart I ofthe screen." t 7 I :1, .1, t l .The louversin't'he bottomjrea B are jconstitued hy t parallel trans'v'e'rsely directed blades, theIupper edge sin? i t faces of which, indicated'at '1, 'arel inclinedt att an angle 1 to the direction of advance down-the screen,- and--are ,j spaced apart by at-tdistance not much in'eXc es's of thel longe est dimension of the largest'raisins'fwhich areto be'processed. The" lower portions of the louvers,findicated at10, maybe generally upright, that is, generally normal to the plane cr me screen as a whole.- Howeyer, the inclination ofthe louvers upper edges l issuch as to ,C0n$ti t1ite;a,slope i t reverse to the direction of advance, and reverse to use will be of assistance in advancing thetnias's. 1 l, t

1 Since, as has been sti'atedabovefthe spacing betw' ii slopev of thegscreen as a whole, if the'same inclinedt'as in the Figure 1 form, and in the latter case the lower po which might dica'ted; a t 1 1, tofprovide surfaces;12 intermediete the slite stems into parallelism with the direction of advanee V b tions '10 are also somewhat sloped reversely to the gene tion :oftadvanc'e; The ripper edges ofthelouveriportions l tare preferablyturned over to; eliminate any sharp edge cat'chaa' barb',' and sojcausexastem to e i halted}; a g; Y I

, The upperbottomsectiOn-Amaybe slightly sh as in whicharefslightly sloped, but which brush 'pa ssing' idowne wardly directed ,stem'f'ends, and ;which collectively con stitute a nearlyimperforate' bottom. 'I'hebihshing-liigis fore they reach the loweredjbottom areazB51The use f the'air jets tatll is optional but it is believed thattheir the louver elements 1 is not greatly in excess of the longest dirnension'of the largest raisins 'beingprocess'ed', perhaps five-eighthsinch', it is evident that these louver spacesare far too small to'encourage or even to permit the crooked three-, fouror five-inch stems to pass backwardly through them, and even shouldan' occasional short stem pass backwardly through them as do the raisins, these small stem fragments'are easilyeliminatedsubsequently from the raisins, as they have no appreciable tendency to cling together in amatted mass.

The screen includes longitudinally directed ridges 3, which intersect the louvers 1 and the surfaces 12,- and extend longitudinally in the direction of advance; they are spaced apart transversely of that direction by a distance which is appreciably less than thelength of the majority of the stems. Their spacing isperhaps one inch apart. They extend uninterruptedly alongrthebottom section A and the bottom section B as well.. These ridgesstand up above the bottom areas by an appreciable distance, perhaps three inches, so that stems whichrest upon-their upper edge, crosswise, are unlikelytoextendso:far down into the channels between'these ridges as to contact the bottom, but rather leave a clear space beneath them, and between them and the bottom.

The function of these ridges, and the parallel channels which they define, is to channelize and effect rearrangement of the stems which are deposited in a helter-skelter mass upon the upper portion of the screen, so that by the time they travel to the discharge end of the screen, many, if not all, the stems have dropped down into the channels between adjacent. ridges, and there have been rearranged from their initial helter-skelter disposition into a disposition wherein they lie generally parallel to and lengthwise of the direction of advance. Only in the process of such rearrangement, and after being thus rearranged, can the raisins drop relatively freely, and can the stems drop down to rest upon the bottom of-the screen. When so rearranged the stems are directed transversely of the surfaces 12, and slide thereover and over the sloping louver surfaces 1 with practically no tendency to catch thereon or to halt their advance. They are interhooked one .with another, so' that they all slide together, but are not-intermeshed appreciably, nor likely to actindependently of the mass. Since the stems'are so much'longer'than the space transversely between ridges 3, it. is impossible for them to turn parallel to the louver spaces, so that-they might drop down therebetween or catch therein.

Some of the shorter stems, thosean inch or less in length, may turn crosswise and drop down. To minimize this it may be desirable to provide low ridge-forming elements 3% which hold some of the medium length stems from turning crosswise to any appreciable extent, which serve to channelize the short stems, and which, like the upper edges of the taller ridges 3, present edges along which stems may ride, leaving a somewhat clear space immediately beneath them into which the raisins may fall, and constitute in efiect a tunnel through which they roll.

In operation the mass of raisins and stems is deposited by way of the feed chute 93 upon the upper portion of the screen, which is set into vibration by the motor 8 and its connected elements. As the vibration continues, the mass of stems and raisins tends to slide down along the upper edges of the ridges 3. Gradually the mass will shake apart, and first raisins, then stems, will begin to drop down into the channels between the ridges. As the mass shakes apart and stems drop down, more raisins will drop free from the mass. The raisins first separated will be deposited upon the substantially imperforate bottom portion A, and raisins later shaken free will be deposited upon the louvered bottom portion B. The lower intermediate ridge-forming elements 30 will halt the stems and support them above the level of the louvers, so as to leave a clear space into which the raisins may drop and down which they may roll, and will serve to channelize somewhat further the shortest stems. By the time the stems and raisins have reached the lower end of the screen most of the raisins will have been shaken free, and 'havebeen dropped or rolled down upon the louvered'bottom' portton, where they reverse their direction otmovement, sliding can be sold at the same price as the raisins'originally separated from the clusters.

Some'of the very shortest of the stems will fall through the louver openings onto'the pan 18. As has beenstated,

this is of no moment,.since they are light, are largely free from barbs, cannot form a mass to enmesh' the raisins, the more so as they are-of small mass and bulk withrelation to the recovered raisins. These short stems are readily separated from the raisins by a subsequent operation.

Air blasts through the jet openings at 11, if employed, will serve to advance the raisins, and any stems which have dropped down, down the slope until the raisins can drop through the louvered bottom area B, and the stems can be aligned with the direction of advance. To a certain extent also these jet openings may serve to advance all stems through the initial portion of the process, and assist in loosening the mixture.

The machine shown in Figure 5 is much the same as that already described. Principally it differs in that the feed is a positive one, advancing the mass and the separated stems positively along a horizontal screen. Only the screening of the raisins depends upon gravity. The admixed mass fed by thefeed chute 93 is engaged by tines 40f anendless belt 40, arranged to travel the length of thescreen. The tines may extend down close to'the bottom of the screen. Their function is merely to advance the mass and stems, while they are being shaken loose and rearranged bythe vibration. They do not materially assist in this loosening or rearrangement. They can be of a length to advance raisins which fall upon thesubstantially imperforate bottom area A, although ordinarily the stems will brush the raisins along until they candrop through the louvered bottom area B.

In operation, it will be understood, the mixture of stems and raisins is advanced in a given direction, by gravity, by air jets, positively, or otherwise, or by two or more such forces combined, along transversely and narrowly spaced ridge edges elevated above a screen bottom, meanwhile agitating the mass. Thereby the mass isgradually shaken apart so that the individual stems can drop down between the ridges, and because of their length relative to the spacing between ridges, and the brushing they receive in area A, become channelized therein to lie in the general direction of the ridges, and the raisins can drop out quite freely onto the screen bottom. The raisins are removed by permitting them to drop through the louver apertures in the screen bottom, with their reversely inclined surfaces, whereas the longer and somewhat interhooked stems can not detach themselves from the mass, to move reversely through the louver spaces, even were they straight enough to do so, and their longitudinal disposition, crookedness, length, and tendency to interhook, and so to move with the channelized mass of stems, in relation to the size and disposition of the louver openings, prevents any such escape of stems other than very short ones.

Such a screen, sixteen inches in width and three feet long. has been operated experimentally at a rate to handle 1300 pounds of mixture in an hour, and it is expected that a screen twenty-four inches wide will handle a ton an hour, day after day. Duplicate screens may be employed in a single machine, and will thus e ual the ca pacity of a specific commercial raisinpacking plant in its allied aspects.

1 claim as my invention: I

l. A machine for separating loose raisins from stems the longest stems; 4

V 5 V c 'with which they are admixed, comprising a screen Whereon to support and along which to advance such a mixture in a given direction, formed with a bottom area which has apertures of a size only su fiici en tly large to pass the raisins, parallel ridges upstanding from said bottom area and extending *inthe direction of advance, and spaced acros's'the screen by distances appreciablyless than the lengthof the majority of stems, means to deposit a tangled, mixture of stems and raisins upon the ridges, to be supf ported thereby above: the screen, and means 'to vibrate the screen in a direction generally normal to its plane, as

I the mixture advances along the rages and the screen. f v

2. A machine for separating loose raisins from stems with which they are admixed, comprising a screen whereon to support and along which to advance such a mixture in a given direction, a plurality of parallellouvers detin ing a bottom area of said screen,'spaced apart in the di- V rection of advance only suificiently'tqlpass raisins between them, and inclined oppositely to t he direction of' advance, means above ander {tending in the direction of advance, and spaced apart transversely by distances appreciably lessthanthelength of; the majority of stems, to align thetadmixed stems generally in th'at same direc- 4 tionas they pass 'over'suchlouyered bottom area, means,

to deposit a tangled mixture ot stems and'raisins upon saidaligning means, above the screen, and :rneanslto agi-' t tatethe mixture in asubstantially vertical direction as it advances towards thedischargeiend of. the'screen.

3. A machine of, the character defined in iclaim ;1, wherein the ridges arejin part'higher, and in: partlower,

V the higher ridges being spacedjaparti by. distances, apt

' 7 'preciably less than the length 0f" the inajority of'sterns,

' ly, the subsequently encountered bottom area} having apen tures of a size only largeenough to pass the'raisins, and V the initially encountered bottom area constituting a floor,

and the lower; ridgesybeing located "intermediate lthe 7 higher ridges; and, each;bei'ng spa'cedjfrom adjacent "ridges by distances lessfltha'n the length of;most of 'the 1 shortstemsu 1i j 4,;A m'achine as set forth in'claim 3,? wherein the highertandtlower ridges alternate, the lower ridges being spaced midway between the two adjacent highenrid'ges; '7 5. A machine of the character defined in claim 1,1

wherein the'ridges, inpart'at least, are of a height above thebottom area to 'locate their upper edges ata distance, above .such bottom area which approaches the length of 6. A machine for separating loose raisins? from stems with which they are admixed, comprising arr in clined f screen Whereon to support and'along which tofadvance such' a mixturein'a' given direction, parallel louver sidirecte' d transversely of the direction of inclination, defin-i ing a bottom arearof said screen,-and spaced apart the direction of'inclina'tion only sufiiciently to pass raisins between them,iridgesupstanding from'said: bottomiarea in uprightparallel planes, extending in the directionpf 1, advance, and spaced apart by distances appreciably less Q than theilength -of the majority of stems, means to de posit a tangled mass of StEIiflSdlPQI'lj'thifllPPEl end crew the ridges, a ndmeans to vibrate the screen ina direc{ tion generally normal to its plane. 7

7. A machine of thecharac'zter defined in claimi6,l wherein the louvers are inclined oppositelyto' the direc- 4 tion of advance.

8. A machine ,ot' the- 'characterfldefined in claim ;6,

wherein the louvers are formed with an'uppe r portion 1 which'is inclined oppositely tothe direction of advance; 1

and a lower portion which is disposed generally normah' ly to the general plane of the screen. a i

'9. A machine for separating raisins frorn' stems' with which-they'are admixed, comprising a screen whereon I to support and along which to advance such-a mixture in a given direction, formed with an initially encountered and a subsequently encountered bottomarea; respectiveto engage and deflect-'stems'directed towards that floor, and formedwith' jet apertures directed in'the' direction of advance, meansto direct 'air'jets through suchrapertures'jrid'ges upstanding from, the bottom areas *of ,the Q i screengextending in upright parallel planes atgsp'acings V appreciablyless than the length of the majority of stems, j means to deposit a tangled mass of stems and raisins upon the'ridges at one'endthereofl'ajnd rneans toagitate the mixturefas' it advances along the;ridges and the sc'reen T V i f I I ReferneesgCited the-file of, patent Q UNITED STATES PATENTS Re. 2,155- Mills Jan.123, 1866 4,600 Church"; June 27, 18,46 24,704 Rollow July ;5,"'1854 V 7 790,704 7 Osborne May '23, 1905 1,820,055 Divolty'" -Aug. 25,,1931' 2,420,941 Fies "M 20,1947, 2,620,064, Thys V VDec.,2 ;1952v i I ,-FOVREIGNV PATENTS I r V a i 374,732,, Ger'many 'Feb.';2 1922 

